The primary objective is to study the interrelationships between electrodermal response measures under different experimental conditions (e.g., orienting, awareness, and conditioning paradigms) among subject populations differing in cognitive functioning (primarily normal, mentally retarded, and schizophrenic). In addition to typical univariate analyses, our prime focus will be to systematically study response measure interrelationships utilizing multivariate techniques of analysis (MANOVA, factor analysis, canonical correlation, etc.) with particular attention paid to the use of response measure interrelationships as dependent variation. The knowledge obtained from this approach will be used to study the different components of the multiple response phenomena in autonomic conditioning with a view toward more complete response specification and in particular to explore the possibility that central processes reflect themselves differently in the interrelationships between response measures.